1. Field of the Invention
The present invention relates to a piston ring device for use in a combustion engine of a vehicle and more particularly to a combined compression ring and oil ring which provides easily assembly and disassembly, and also reduces rubbing loss which, in turn, minimizes power loss.
2. Description of Related Art
Various types of piston ring devices for use in the combustion engine of a vehicle are known in the art. Generally, a combustion engine of a vehicle produces power by causing the combustion of a fuel-air mixture in the combustion chamber. That is, the combustion in the engine causes the piston to move up and down in the cylinder. The up and down (vertical) movement is converted by a crank to revolutional movement, and thus, a firm contacting relationship between the piston and the cylinder must be continuously maintained. Accordingly, in conventional devices, a plurality of piston rings are utilized to maintain a firm relationship between the cylinder and the piston.
As shown in FIG. 1, a conventional piston ring utilizes a pair of compression rings 108 and 110 disposed in a pair of compression ring gloves 102 and 104, respectively, and also an oil ring 112 disposed in an oil ring groove 106 for firmly contacting and sealing the piston 100 with the inner wall of the cylinder 101. The device may include four piston rings. The pair of compression rings 108 and 110 prevent the creation of a blow-by of the expanding gas, and the oil ring 112 prevents engine oil from entering into the combustion chamber.
However, such a conventional piston ring system suffers from a number of problems. For example, since three rings 108, 110 and 112 are independent, it is difficult to assemble and disassemble three separate rings 108, 110 and 112, which introduces power loss and an overall bad influence to the piston which becomes light because each of the rings 108, 110 and 112 are rubbed independently.